Re: [PATCH] xtensa: Increase size of gcc stack frame check

[Guenter Roeck]

On 9/11/21 8:05 PM, Max Filippov wrote:
> On Sat, Sep 11, 2021 at 7:52 PM Guenter Roeck <linux@xxxxxxxxxxxx> wrote:
> > xtensa frame size is larger than the frame size for almost all other
> > architectures. This results in more than 50 "the frame size of <n> is
> > larger than 1024 bytes" errors when trying to build xtensa:allmodconfig.
> >
> > Increase frame size for xtensa to 1536 bytes to avoid compile errors
> > due to frame size limits.
> >
> > Cc: Chris Zankel <chris@xxxxxxxxxx>
> > Cc: Max Filippov <jcmvbkbc@xxxxxxxxx>
> > Signed-off-by: Guenter Roeck <linux@xxxxxxxxxxxx>
> > ---
> >   lib/Kconfig.debug | 2 +-
> >   1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
> > index ed4a31e34098..afad11e57d6b 100644
> > --- a/lib/Kconfig.debug
> > +++ b/lib/Kconfig.debug
> > @@ -346,7 +346,7 @@ config FRAME_WARN
> >          int "Warn for stack frames larger than"
> >          range 0 8192
> >          default 2048 if GCC_PLUGIN_LATENT_ENTROPY
> > -       default 1536 if (!64BIT && PARISC)
> > +       default 1536 if (!64BIT && (PARISC || XTENSA))
> >          default 1024 if (!64BIT && !PARISC)
>
> Shouldn't that line also be changed to
>    default 1024 if (!64BIT && !(PARISC || XTENSA))
> ?

I could do that, but I tested it and it looks like the evaluation
is top-down, so it didn't seem necessary or useful. For example,
the default value is 2048 for 32-bit systems (such as arm, riscv32,
or i386) if GCC_PLUGIN_LATENT_ENTROPY is enabled, even though the
line with the default of 1024 matches as well.

Thanks,
Guenter